How to change the Spark Plugs on a Fiat 500​

There's nothing like being able to save some cash by carrying out work on your own car. It makes sense to leave the complicated stuff to the specialists of course, but there is no reason why, with a little guidance, you can't get stuck into some maintenance to keep your Fiat 500 ticking over nicely. As well as helping you to save money and keep down your day-to-day running costs, it can also be a really rewarding thing to do. Changing spark plugs is one of those jobs that you can do at home with just a bit of knowledge, the right tools, the correct replacement parts and a bit of free time. First off though it is best to understand exactly what role spark plugs perform and why exactly they make up part of your car's engine.​

Why does my Fiat 500 need spark plugs?

Spark plugs play a crucial role in all car petrol engines, regardless of make or model. These devices form part of the Fiat's ignition system and are used to create an electrical spark that ignites the air and fuel mixture in the car's cylinders, which in turn starts the vehicle. It is important for a plug to create a spark at just the right moment in order for the process to work properly. If a spark plug is not firing at the right time, or if the spark is weak, the air/fuel mixture will not ignite correctly. This is likely to lead to problems when starting a cold engine and will also affect the performance of the car, resulting in a lack of performance and a drop in fuel economy. So not only can you end up being late as your car won't start thanks to ineffective spark plugs, they can also start costing you money by forcing you to visit the petrol pumps more often.

When do I need to replace my spark plugs?

Spark plugs found in modern engines are designed to last many tens of thousands of miles. It's important to remember however that the life of a plug depends on the type of material that it is made from and its condition. Even when the strongest materials are used, deposits build up on the surface of spark plugs as a result of the ignition process and this can affect their performance. If you're trying to get to lectures at college or uni and your car won't start first time, then there's a chance that your spark plugs are to blame.

How will new good quality spark plugs affect my Fiat 500's performance?

By ensuring your Fiat's spark plugs are up to the job, you'll benefit from consistent fuel combustion, improved fuel economy, smooth and reliable starts and reduced CO2 emissions. The good news is that replacement spark plugs are inexpensive and once you have gone through the process of replacing them once, you'll have no problems repeating the process in the future if necessary. What's more, a successful spark plug change might even spur you on to learn more about carrying out maintenance work on your Fiat 500.

Prepare

Once you're sure that your plugs need replacing, the first thing to do is prepare to carry out the job. Make sure you have clothes suitable for working in and that the engine of the car is cold. Most importantly, ensure you have a new set of spark plugs that are compatible with your model of Fiat 500. There are a number of powertrains available, such as the 1.2-litre and 0.9-litre TwinAir 85bhp and 105bhp petrol engines. In addition you'll need tools including a socket spanner and torque wrench to complete the work.

Gain access to the spark plugs

First off you may need to clear a path in order to get access to the spark plugs. You may find that you need to remove the car's HT leads and other parts before work can begin. Draw diagrams of where the various parts go so you'll be able to replace them later without any problems.

Clean the area

Before removing the old spark plugs, take a moment to clear any debris away from the area. If you have a can of compressed air to hand then put on eye protection and blow the area clean to ensure no dirt manages to fall into the cylinders once the spark plugs have been removed.

Removing the old plugs

Work on one spark plug at a time to reduce confusion about which wire goes where once it's time to put everything back. If you're not used to car maintenance then the simpler you can make things the better. Do not yank the spark plug wire from the cylinder, rather apply gentle pressure to the boot of the wire until it comes loose. It's now time to use your socket spanner to unscrew the plugs and remove them.

Inserting the new plugs

Before inserting your new plugs into their sockets, add a small amount of copper grease onto the threads of each to make the replacement process simpler. You can make use of a piece of flexible hose to start off the process of screwing in your new spark plugs, before turning to a torque wrench to tighten the plugs off. You'll then need to put the spark plug wires back as they were.

Replace as found

You'll need to repeat the whole process for each of the engine's spark plugs. Remember to make sure once you have finished the work that any parts you moved in order to get access to the area, for example the car's HT leads, have been replaced correctly.

When things don't go to plan

While the process of changing sparks plugs on the Fiat 500 can be done quickly and efficiently when you have mechanical experience, if you find that you're uncomfortable with the process then it is best to stop and turn to the services of an expert. Far better to admit defeat and get your spark plugs replaced professionally without spending much money, than to have to fork out to cover an expensive repair bill because you've unintentionally damaged your vehicle.

Contact Us

Welcome to Thames Motor Group. To optimise your experience, cookie settings on the website are set to allow all cookies. By continuing your journey throughout the website, you consent to this. You can change these settings here.

Thames Motor Group (Slough) Limited and Thames Motor Group (Tunbridge Wells) Limited are Appointed Representatives of AutoProtect (MBI) Limited which is authorised and regulated by the Financial Conduct Authority. AutoProtect's FCA Registered Number is 312143. AutoProtect's permitted business is arranging, advising and administering non-investment General Insurance Contracts.